Quaternary ammonium compounds as accelerators of polymerization of ethylenic compounds



United States Patent QUATERNARY AMIVIONIUM COMPOUNDS AS ACCELERATORS OFPOLYMERIZATION OF ETHYLENIC COMPOUNDS Earl E. Parker, Milwaukee, Wis.,assignor to Pittsburgh Plate Glass Company, Allegheny County, Pa., acorporatron of Pennsylvania No Drawing. Application October '15, 1953,

Serial No. 386,387

8 Claims. (Cl. 260-454) and others.

The invention has especial relation to a novel catalyzation systemdesigned to eflect smooth and rapid cure of interpolymerizable mixturesof the foregoing polyesters and monomers.

It has heretofore been recognized that liquid monomers containing theC=CH2 group attached to a negative radical, as above described, wereadapted when heated, to undergo addition polymerization to form valuableresins. It has also been recognized that polyesters of dihydric alcoholsand alpha-beta ethylenic dicarboxylic acids were capable of additionreactions to form resinous products. Both of these reactions wererelatively slow, so long as the esters or monomers per se were employed.This was true even though free radical initiators such as benzoylperoxide or the like were incorporated for purposes of accelerating thereaction involved in polymerization.

It has further been recognized that mixtures of the fusible polyestersabove described and the monomers soluble therein, were capable of farmore rapid reaction than either of the components taken singly. Forexample, mixtures of (A) polyesters of glycols such as diethylene glycoland fumaric acid with (B) monomers such as styrene, readily undergointerpolymerization reactions to form infusible, insoluble (thermoset)addition products even at moderate temperatures and in the absence ofsubstantial pressure. These interpolymerizable mixtures lend themselvesquite effectively to the formation of castings and can be employed tocoat or to impregnate preforms and fabrics of fibrous reenforcingmaterials such as glass fibers, asbestos and many othermaterials.

Indeed, the interpolymerizable mixtures are highly reactive and formpolymer products so rapidly that the mixtures cannot be stored for anyappreciable period of time without a strong tendency for them to undergopremature gelation and setting. This is especially true where themixtures are subjected to somewhat elevated temperatures. Since mixingof the polyester and the monomer is often conducted with the polyesterheated to impart fluid ity thereto, there is danger of gelation evenwhile the monomer is being mixed into the polyester.

In order to obviate these difliculties, it was early proposed toincorporate into the components of the interpolymerizable mixturesubstances termed inhibitors, which 1 in the reaction. Thesecharacteristics in the quaternary 2,740,765 Patented Apr. 3, 1956 ICC'interpolymerization reaction, especially at moderate temperaturesinvolved in the preparation of the mixtures, or in the storage of thelatter after preparation. Among the materials so proposed for use asgelation inhibitors were the quinones and hydroquinones; also, catecholsand sub stituted catechols such as tertiary-butyl catechol were oftenused. These quinonic or phenolic type of inhibitors were persistent andpowerful inhibitors; in fact, they continued to exert a very strongretarding eitect on interpolymerization even after the free radicalinitiators such as cumene hydroperoxide, or tertiary-butyl hydroperoxidewere incorporated, and untilthe temperature of the polymerizable mixturewas raised to a relatively high level. These persistent retardingefiects were often highly undesirable, especially in the use of theinterpolymerizable mixtures in casting operations. In mixturescontaining these inhibitors alone, exothermal temperature was oftenexcessive and cracked or discolored products resulted.

In a prior patent, U. S. 2,593,787 to Earl B. Parker, it has beendisclosed that certain salts of quaternary ammonium compounds alsoconstitute valuable gelation inhibitors in interpolymerizable mixturesof (A) polyesters of alpha-beta ethylenic dicarboxylic acids andpolyhydric alcohols and '(B) monomers, containing a C=CH2 group.

These quaternary ammonium salts when incorporated into themonomer-polyester mixtures were highly effective over a relatively broadrange of temperatures, so long as free radical initiator type catalystssuch as benzoyl peroxide were not included in the mixture. However, whenthe latter were incorporated, the interpolymerizable mixtures wouldquickly start to polymerize and thus to gel and set into their.hardened, infusible, insoluble or thermoset state. This reaction beganat a relatively low temperature and proceeded smoothly and withoutexcessive rise of the temperature due to exothermal heat productionammonium saltswere-highly desirable especially in the art ofcas'ting theinterpolymerizable mixtures. For this reason, they have enjoyedextensive use.

The foregoing patent to Earl E. Parker further discloses the use ofquinones and hydroquinones with the quaternary ammonium salts forgelation inhibiting purposes, but the amount was no more than a trace.In the use of the foregoing mixtures of quinones and hydroquinones andquaternary ammonium salts as gelation inhibitors in theinterpolymerizable mixtures the quaternary ammonium salt was employed ina great y predominating amount and was relied upon to maintain storagelife of the mixture.

The highly surprising discovery has now been made that ininterpolymerizable mixtures of (A) polyesters ofdihydric alcohols andalpha-beta ethylenic dicarboxylic acids and (B).monomers containing a 0H2 group, which mixture has been stabilized with a quinonic or phenolicstabilizer and therefore tends to gel but slowly when heated in thepresence of peroxide or hydroperoxide catalysts; the quaternary ammoniumsalts act as powerful activators or synergists or adjuvants, to attaingelation, often in a fraction of the time required in their absence. Atthe same time, the so-called tank life or capacity of the mixtures .towithstand storage after the free radical initiator is added issatisfactory. It is a further important advantage of the invention thatthe gel times of mixtures of polyesters and monomers containing properamounts of a phenolic stabilizer and quaternary ammonium salts, ex-

hibit but slight tendency to drift during relatively long,

; exert their influence as stabilizers during the periods of storage ofthe interpolymerizable mixtures. Naturally, there is no synergistic, oractivating eflect' until a free radical initiator such as a peroxide orhydroperoxide is added. For these reasons, the quaternary ammoniumcompound may be added concurrently with or subsequent to the addition ofthe peroxide.

It will be appreciated that where interpolymerizable mixtures are madeup with but minimal amount of an inhibitor or an inhibitor pair, asherein disclosed, the inhibitor may tend to become depleted after aperiod of storage. In order to attain a longer tank life and a quick geltime in such mixture, appropriate amounts of the inhibitors (quinonic orphenolic and quaternary ammonium salt) may be added to the mixture at,or at about the time the peroxidic catalyst or free radical initiator isadded.

The several components and the range of equivalents thereof in theinterpolymerizable mixtures which may be treated in accordance with thisinvention, will now be more extensively elaborated upon:

The interpolymerizable component (polyesters and monomers) which may beemployed, may be any of these discussed in the foregoing Parker patentand the latter may be employed as a source for the determination ofappropriate interpolymerizable mixtures. Needless to say, any of theequivalents (many of which are well known) of the materials disclosed inthe patent may also be employed, since they all depend upon a recognizedmode of interac tion between the ethylenic groups of the polyester andthe corresponding terminal C=CH2 groups in the monomers.

In preparing polyesters which may be employed in the practice of thepresent invention, the polyhydric alcohol component may compriseethylene glycol, diethylene glycol or propylene glycol. It is alsosom'etirn'es advantageous to substitute for some of these glycols apolyethylene glycol such as the commercial Carbowaxes.

Polyethylene glycols such as the Carbowaxes are understood to havemolecular weights above 300. Those most useful for this invention haveweights below 4000 and preferably are in a range of about 1000 to 2000,e. g., 1500.

The polycarbolylic acid components should comprise an alpha-betaethylenic polycarboxylic acid such as maleic, fumaric or itaconic acidor the well-known derivatives of these polycarboxylic acids havingethylenic unsaturation in alpha-beta relation to a carboxyl. Polybasicacids such as aconitic acid, tricarballylic acid or citric acid may alsobe employed. A plurality of acids ethylenically unsaturated in thealpha-beta position may be mixed with each other, if so desired. In manyinstances, it is desirable also to include a dicarboxylic acid free ofethylenic unsaturation. This latter type of dicarboxylic acid includesphthalic acid or terephthalic acid, which although-they contain doublebonds in the benzene ring, do not undergo addition reaction with monomercompounds and may, therefore, be considered as being the equivalent ofsatu rated compounds. Likewise, aliphaticdicarboxylic acids such assuccinic acid, adipic acid, sebacic acid, or azelaic acid may besubstituted for a part of the alpha-beta ethylenically unsaturateddicarboxylic acid. The proportion of the non-ethylenic acid withrespectto the alpha-beta ethylenic component is susceptible of wide variation.A molecular proportion of 0.25 to 10 or 12 moles of the non-ethyleniccomponent is suggested as being an appropriate range.

In preparing the polyester a small excess (usually or per cent) of thedihydric alcohol is usually employed. The conditions of esterificationreaction are those conventionally employed in preparing polyesters. Forexample, the mixture of the polyhydric alcohol and the dibasic acid oracids is heated in a closed container or under an inert atmosphere untilwater of reaction is expelled from the system, which usually occurs in atemperature range of about 150 to 200 C. The reaction is continued untilwater ceases to evolve or until the acid value is reduced to areasonably low point, e. g., within a range of about 5" to or until themixture becomes highly viscous or even solid when it is cooled. Usuallythese conditions are attained in a period of 2 to 20 hours. In anyevent, the reaction is concluded before the product becomes infusibleand insoluble because of the advanced stage of polymerization.

The monomers may conveniently be selected from those listed in theforegoing patent or they may be selected from the following generallist:

(i) Monoolefinic hydrocarbons, that is, monomers containing only atomsof hydrogen and carbon, such as styrene, alpha-methyl styrene,alpha-ethyl styrene, alphabutyl styrene and vinyl toluene, and the like;

(2) Halogenated monoolefinic hydrocarbons, that is, monomers containingcarbon, hydrogen and one or more halogen atoms such asalpha-chlorostyrcne, alpha-bromostyrene, 2,5-dichlorostyrene,2,5-dibromostyrene, 3,4-dichlorostyrene, 3,4-difiuorostyrene, ortho-,meta-, and parafluorostyrenes, 2,6-dichlorostyrene, 2,6-difiuorostyrene,3- fluoro-4-chlorostyrene, 3-chloro-4-fluorostyrene,2,4,5-trichlorostyrene, dichloromonofluorostyrenes, chloroethylene(vinyl chloride), 1,1-dichloroethylene (vinylidene chloride),bromoethylene, fiuoroethylene, iodoethylene, 1,1- dibromoethylene,1,1-difluoroethylene, 1,1-diiodethylene, and the like;

(3) Esters of organic and inorganic acids such as vinyl acetate, vinylpropionate, vinyl butyrate, vinyl isobutyratc, vinyl valerate, vinylcaproate, vinyl enanthate, vinyl benzoate, vinyl toluate, vinylp-chlorobenzoate, vinyl o-chlorobenzoate, vinyl m-chlorobenzoate andsimilar vinyl halobenzoates, vinyl p-methoxybenzoate, vinyl o-methoxybenzoate, vinyl p-ethoxybenzoate, methyl mcthacrylate, ethyl methacrylate,propyl methacrylate, butyl methacrylate, amyl methacrylate, hexylmethacrylatc, heptyl methacrylate, octyl methacrylate, decylmethacrylate, methyl crotonate, ethyl crotonate and ethyl tiglate,methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate,butyl acrylate, isobutyl acrylate, amyl acrylate, hexyl acrylate,Z-ethyl-hexyl acrylate, heptyl acrylate, octyl acrylate,3,5,5-trimethylhexyl acrylate, decyl acrylate and dodecyl acrylate,isopropenyl acetate, isopropenyl propionate, isopropenyl butyrate,isopropenyl isobutyrate, isopropenyl valerate, isopropenyl caproate,isopropenyl ennnthate, isopropenyl benzoate, isopropenylp-chlorobenzoatc, isopropenyl o-bromobenzoate, isopropenylm-chlorobenzoate, isopropenyl toluate, isopropenyl alpha-chloroacetateand isopropenyl alpha-bromopropionate;

Vinyl alpha-chloroacetate, vinyl alpha-bromoacetate, vinylalpha-chloropropionate, vinyl alpha-bromopropionate, vinylalpha-iodopropionate, vinyl alpha-chlorobutyrate, vinylalpha-chlorovalerate and vinyl alpha-bromovalerate;

Allyl chlorocarbonate, allyl formate, allyl acetate, allyl propionate,allyl butyrate, allyl valerate, allyl caproate, diallyl phthalate,diallyl succinate, diethylene glycol bis- (allyl-carbonate), allyl3,5,5-trimethylhexoate, allyl benzoate, allyl acrylate, allyl crotonate,allyl oleate, allyl chloroacetate, allyl trichloroacetate, allylchloropropionate, allyl chlorovalerate, allyl lactate, allyl pyruvate,allyl aminoacetate, allyl acetoacetate, allyl thioacetate, diallyl-3,4,5,6,7,7-hexachloron endomethylene tetrahydrophthalate, as well asmethallyl esters corresponding to the above allyl esters, as well asesters from such alkenyl alcohols as beta-ethyl allyl alcohol,beta-propyl allyl alcohol, 1- buten-4-ol, 2-methyl-buten l-ol-4,2(2,2-dimethylpropyl l-buten-4-ol and l-pentenel-ol;

Methyl alpha-chloroacrylate, methyl alpha-bromoacrylate, methylalpha-fiuoroacrylate, methyl alpha-iodoacrylate, ethylalpha-chloroacrylate, propyl alpha-chloroaci'ylate, isopropylalpha-bromoacrylate, amyl a]p ha-chloro acrylate, octylalpha-chloroacrylate, 3,5,5-trimethylhexyl alpha-chloroacrylate, decylalpha-.chloroacrylate, methyl alpha-cyano acrylate, ethyl alpha-cyanoacrylate, amyl al pha-cyano ac'r'yla'te and decyl alpha-cyano acrylatetQimsux malsateis ieth tana eate ll taateatsua methyl fumarats, .a lrl s-slt hyleluta- Ql fli 1 .Qraaui9... tt le u9l .as ss x suituta.irt lsmlqsiguilt stltsstrlguit ile stqtsuitti s, .aud the like;

' .6) A215 291! a .astxli a214 ,mr haqrrlic acid, crotonic acid,3-butenoic acid, angelic acid, tiglic acid and thelike;

t amide suchasacrylamide lP s N s i lastxj l hehkef t a-meth ylnag lt or1 ara se b u i fill in the absence of gelation inhibitors, quicklyitoinduceipremature gelation upon dt s q 9 t e E PPBE E iHW t e true evenin {if free racli dingly, it is preferred to ts 'i -E E QQFRQPFxQL.ponents of the mixture. quinonic or phenolic class include:

IA It :These are but examples. ,Otheriphenolic inhibitors mayabe used intheir place. tFor-exam'ple, :BJsopropyl catechol which, withinitself, isan excellent inhibitor may .be.emp1 oyed.

Naturally, the .gelation.inhibitor-remains in the-solution of polyester.and interpolymerizable i-monomer .and may conveniently constitute an:inhibitor ofmgelation'durin'g subsequent storage of ;the materialtbefore' the'tlatteris,

actually used. :The amount. of. thelphenolic, inhibitor required in themixture during the .mixing stage.isisusceptibleof variatioubutconveniently is in a range of about 0.91" p 0:1 per cent-byWeightbasedupon thepolyester component of the mixture. 'It preferablyshould e at least 10 percent by weight of the quaternary ammomum sa taam -b e muel a lflqflienmarap a cen imeter thau he a t T -im s ymeriz lmix eself-equa e elph st et n di ar -w l sifls-an mqae rs remain: ing aninhibitoras above. described, maybestored over substantial periods oftime, for exarnple, several weeks or even months without danger ofpremature gelation.

196 of the peroxidic type audgray be either a peroxide or ahydroperoxide. Appropriate free radical initiators elude:

sr esrsx dr- Tertiaiy] tyl dropsrexid Y Qliar =hul 9Psmid AcetylpergxideLauroyl-peroxide uua elh dro ema s eetc- These may be utilized.inamounts of about 0.1 to 5 per cent by weight based upon the'zmixturlelNaturally, the amount of the peroxygenlcatalyst applicable in thepractice of the inventionfiwillivary with the activity oftli eparticular salt and with the amount of quinone type or phenolic typeinhibitor .present in .the interpoly-mriiable mixture. They allconstitute catalysts of interpolyrri'eria ation at elevatedtemperatures'and are desirable in order to attain a completeand thoroughcure 'in themixturtm within reasonable periods of time and at reasonabletemperatures. i

It is an advantage o f=the-present invention that where a quaternaryammonium'saltis'employed in accordance with the provisions ofthepresentinvention ,as an adjuvant for the i nterpolymerization reaction evenrelatively l Filiflfifillhfi sue elhrdm erexitlws b etle cessfullyemployed 'to attain a high rate of int erpplymerization. Cumenehydroperoxide is'us'ually considered v tp be a relativelyyslow catalystthough it; is comparatively inexpensive. Thereforeit is highly'desirableto obtain activation 1 thereof by (the use (if-the quaternaryammonium-salt. The amount-of the quaternary ammonium comppund willvaryusually within a range of about 0;0O1

to 01 1 percentbased upon the polyester component of the interpqlymerizable mixture. Ifareasonable excess of adatfliary amei aiu s l isms-em ithe int polymerizable mixture above that required to produce maximumactivating or synergistic efiect no particular harm is done. Therefore,within reason, theupper limit of uaternary amoniuin s'altis not crit ical. l V

' 1 .qnsier' tha th q aterna e urlszy la j ashur 'tse p i sist w th ut.s mi altqeasf .tuei qis $irs ha th v aa emsryam uoa u have ni fzi rdese-of splubi ty n-th interpolymerizable mixture. Some of the quaternaryammonium salts are directly soluble in the polyester or mixtutes of thepolyester and monomers. .Often it' is desi'rable toprovide what inetfe'ct constitutes a masterbatch of interpolymerizable mixture and aconcentration of quaternary'animonium salt. Such master batch carrbeobtained by addition of an excess of quaternary an1- Itwnium a t the leneqlys te and t e add a me t-wis -.Strttil pvr iae e fth maste ba masequently be added totliemain .batchiof polyester and monomer containinga quinone or phenolic inhibitor in substantial amount. lnlsomeinstances,quaternary amuranium sal ar so ab tin m w s h esst re a ut qa titer-rein th la te se e ad ed to she interpolyme'rizable mixture. In still.otherqinstances, Tthe sa et a amm aiam sal a be i s v i a cu Q so ren liha sh ewfmmwhi -no w re tive .of thedesiredresin, andthesolution can beachled to the polyester, the monomer, or the mixture of se- APPEQPIQE.-.q at rna amm n um compound pan be selected byreferencertotheforegoingfatent .mciallrhrrefsmn e to Ta l G of-the set-11 quate nar e aenium s ltsinclude the 7 7 TABLE B Trimethyl benzylammonium chloride Trimethyl benzyl ammonium bromide Triethyl benzylammonium chloride Tripropyl benzyl ammonium chloride Tributyl benzylammonium chloride Cetyl trimethyl ammonium chloride Octadecyl trimethylammonium chloride Trimethyl benzyl ammonium chloride Lauroyl pyridiniumchloride Phenyl trimethyl ammonium chloride Tolyl trimethyl ammoniumchloride Benzyl trimethyl ammonium phosphate Benzyl trimethyl ammoniumiodide Ethyl pyridinium chloride Phenyl trimethyl ammonium chlorideOctyl' trimethyl ammonium bromide Ethylene bis(pyridinium chloride)Ethylene bis(trimethyl ammonium bromide) Trimethyl benzyl amoniumoxalate Trimethyl benzyl ammonium maleate Trimethyl benzyl ammoniumtartrate Trimethyl benzyl ammonium lacetate Trimethyl alkylbenzylammonium chloride Diisobutyl phenoxy ethoxy ethyl dimethyl benzylammonium chloride The acids from which the salts are derived should beat least as strong as acetic acid and should be non-oxidizing. The saltsshould be soluble in the mixture. As demonstrated in the examples tofollow, other quaternary ammonium salts than those indicated in Table Bmay be used as synergists, activators, or accelerators in theinterpolymerizable mixture.

The application of the principles of the invention is illustrated by thefollowing examples:

Example I This example constitutes a control illustrating the gelationof an interpolymerizable mixture of an alpha-beta ethylenicallyunsaturated ester and a monomer which has been stabilized withhydroquinone without the use of a quaternary ammonium salt as a gelationcatalyst. In the example, a polyester which was obtained by condensationof equal moles of maleic acid and phthalic acid with a silightstoichiometric excess of propylene glycol was used. This was dividedinto several samples.

SAMPLE I Six hundred and fifty parts by weight of this polyester wasmixed with 350 parts by weight of styrene and the mixture was stabilizedagainst premature gelation by the incorporation of 013 part by weight ofhydroquinone.

SAMPLE II A second sample was prepared of identical composition exceptthat the hydroquinone was replaced by 0.195 part by weight of4-t-butyl-catechol.

SAMPLE III A third sample was prepared identical to the first exceptthat the hydroquinone was replaced by 0.13 part by weight of chloranil.

All of these samples were quite stable against premature gelation andcould be stored for long periods of time.

In order to determine their curing characteristics, a test portion ofeach of the foregoing compositions, was incorporated with a free radicalinitiator namely, tertiarybutyl hydroperoxide, as a catalyst and in anamount of 1 per cent by weight based upon the interpolymerizablemixture. Each of the portions was then placed in a test tube which washeated in a water bath at a temperature of 180 F. The time required forgelation'after the samples had been placed in the bath was taken as thegel time. These gel times were as follows:

Seconds Sample I 2575 Sample II 2135 Sample III 1229 Example II SecondsSample I 1353 Sample II 1540 Sample III 835 The following examplesillustrate the use of quaternary ammonium salts as synergists oractivators in the interpolymerizable mixtures.

The samples were heated on a water bath at 180 F., at which temperatureinterpolymerization proceeds rapidly to provide solid resinous productsshowing the utility of the materials for making castings in molds. Thegelling of the mixtures was an observable phenomenon, and the cure andthe time thereof shows the rate of cure. Shortly after gelling, themixtures were cured to a hard, thermoset, insoluble state; but could bebaked at to or 200 C. further to harden them if desired.

Example III In this example, a quaternary ammonium salt knowncommercially as Quaternary O was added to a set of samples prepared inaccordance with the provisions of Example I. Quaternary O is understoodto be represented by the formula In the formula, radicals R are hydrogenor alkyl and the molecular weight thereof is to selected that the totalmolecular weight is about 450. In the samples of this example, thepercentage of Quaternary O was varied, one sample containing 0.01 percent of Quaternary O, the second containing 0.03 and the thirdcontaining 0.05 per cent by weight (these percentages of Quaternary 0are based upon the total resin components). These samples were thenintroduced into a test tube as in the preceding examples and weresubjected to the same curing conditions. The gel time in seconds of thesamples con taining 0.03 per cent by weight based upon the total resinof Quaternary 0 were respectively as follows:

Sample I 846 (control 2575). Sample II 810 (control 2135). Sample III596 (control 1229).

It is thus obvious that the gel time in seconds was cut by more than 50per cent by the introduction of the Quaternary O. The cured productswere hard, clear and crack free. The mixture could be used to makecastings or to impregnate or coat preforms and fabrics.

Example IV This is essentially a repetition of Example III except thatthe base compositions are taken from the composition of Example II andemploy the cumene hydroperoxide catalyst of the latter example as thefree radical initiator. With 0.01 per cent by weight based upon thetotal resin of Quaternary O the ,gel times in seconds of the three basematerials were respectively:

Sample I 603 (control 1353). Sample II 690 (control 1543). Sample III417 (control 835).

The products were clear, hard, sound castings.

' Example V In this example a quaternary ammonium compound knowncommercially as Oronite Quaternary Compound ATM-50 was added to astabilized and catalyzed composition as disclosed in Example I. Theformula of Oronite Quaternary Compound ATM-50 is understood where R isan alkyl radical containing 8 to 18 carbon atoms. Tests were runrespectively with quantities of 0.01, 0.03, and 0.05 per cent by weightbased upon the total mixture of the quaternary ammonium compound. Whenthe samples contained 0.01 per cent, the gel times in seconds wererespectively:

Seconds Sample I 454 Sample II 486 Sample III 338 The products wereclear, sound castings.

Example VI Sample I 288 Sample II 315 Sample III 177 The productswereclear, sound castings. 3

Example VII In this example, a commercial quaternary ammonium compounddesignated as cetylbenzalkonium chloride was employed as a synergist oradjuvant in a stabilized and catalyzed composition prepared inaccordance with Example I. ,It is understood that the cetylbenzalkoniumchloride of this example include alkyl radicals of variable lengthsubstituted in or attached to the nitrogen atom. Tests were runrespectively with 0.005, 0.01, 0.03, and 0.05 per cent of the quaternaryammonium compound and it was determined that the gel times were near aminimum with 0.03 per cent of the synergist. With this amount present,the gel times in seconds were respectively:

Sample I 320 Sample II 506 Sample III 358 The products cured to provide.clear, sound castings.

Example VIII The synergist (cetylbenzalkonium chloride) of Example VIIwas employed in the inhibited. mixture containing cumene hydroperoxideas prepared in accordance with Example II. Tests were run with sets ofsamples containing respectively 0.005, 0.01, 0.03, and 0.05 per cent ofthe,quaternary ammonium compound and it was determined that the geltimes were near a minimum with 0.01 per cent of the'cetylbenzalkoniumchloride. At this value the gel times in secondswere respectively:

Sample I 320 Sample II 343 Sample III 169 l The products were clear,sound castings The mixture could be used to impregnate glass fabrics andother fibrous bodies. i

Example In this example, the stabilized compositions prepared inaccordance with Example I'containing tertiary-butyl hydroperoxide as acatalyst-were activated in order to obtain a reduced gel time by theaddition of lauroyl pyridinium chloride. Tests were conductedrespectively with 0.005, 0.01, 0.03, and 0.05 'per cent by weight basedupon the total resinifiable mixture of the lauroyl pyridinium chloride.With 0.01 per cent of the latter compound,

the gel times in seconds were substantially at a minimum and are herebytabulated as follows:

Sample I 324 Sample II 422 Sample II The castings were clear and sound.

Example X v This is a duplication of Example IX except that thecumene-hydroperoxide was employed as a free radical initiator inaccordance with the disclosure of Example'II. With 0.005 per cent byweight based upon the resinifiable mixture of the synergist, the geltimes in seconds of the respective samples were:

Sample I 314 Sample I! 310 Sample III v189 Example XI In this examplethe free radical initiatorwas tertiary butyl hydroperoxide l per cent).A commercial quaternary ammonium compound sold under the trade name ofHyamine 1622 was employed as a synergist. This is and is sold by theRohm & Haas Company. Tests were conducted respectively with 0.005, 0.01,0.03, and 0.05 per cent by weight of Hyamine 1622 based upon the totalresins and optimum or near optimum results were obtained with 0.01 percent of the same. At this concentration, the gel times in seconds forthe three samples were respectively:

Sample I- 390 Sample II 546 Sample III 338 Example XII This is arepetition of Example XI except that the commercial quaternary ammoniumcompound known as Hyamine 2389 was employed asthe synergist. Hyamine2389 is understood to be of the formula:

C H: CH;

Sample I 328 Sample II 7 A 352 Sample III 303 Example XIII Thi xamp e sessenti ly repetition of Example X u wi h cume e h d spe xiqs o E a p IIs e free radical initiator. With 0.01per cent by weight based 1129" t mXtur pf-Hyami e 1.62 as dis losed in Exmpl XL, h s t time i ssconds f ts p were I "'f"" k Sample II 312 Sample III 173 Ersmrle XI This is arepetition of 'Example XIII with Hyamine 2389 as the synergist and the,cumene hydroperoxide as the catalyst. With 0.01 percent by weight ofHyamine 2389, the gel times in seconds of the samples were respectively:

Sample I- 335 Sample II i A i h 33.8 Sample III 194 Example XV In thisexample a commercial quaternary ammonium compound,-narnely trimethylbenzyl ammonium chloride (disclosed in the forementioned Parker patent)was employed as a synergist. In the use of thissynergist, 650 parts byweight of a polyester of equal moles of maleic anhydride and phthalicanhydride with propylene glycol in slight excess of stoichiometricproportion was employed. To this was added 350 parts byweight of styreneand 1 part by. weight of trimethyl benzyl, mmonium chloride. Thismixture (designated as MB) was employed as a master batch for theintroduction of trimethyl benzyl ammonium chloride into a stabilized anda catalyzed mixture prepared in accordance with the provisions ofExample I. Master batch in amounts respectively of 2.5-, 5, 7.5 and 10per cent by weight based upon the total resins were employed in sets ofsamples. When 7.5 per cent by weight of the master batch was employed,the gel time of the interpolymerizable mixture was near a minimum. Withthis proportion of the master batch, the gel time in seconds wasrespectively:

Sample I"--. 202 Sample II s 319 Sample IIL. 225

. Example XVI This example is essentially a repetition of Example XVexcept that cumene hydroperoxide is replaced by tertiary-butylhydroperoxide. In'this example, gel times were attained with about 10per cent by weight of the master batch. With this proportion of masterbatch the gel times in seconds respectivelywere:

Sample I V 320 amp 1.1 363 Sample III 266 For purposes of moreconvenient comparison of the test data for the several examples, theessential features thereof are hereby presented for all-- 01% theexamples in tabular form:

Gel Time in Seconds Sam Catalyst Activator or Synerglst I II III 1%t-butyl hydro- 2, 575 2,135 1, 229

peroxide.

D 0.01% Quaternary 1, 030 1, 607 0.03% Quaternary 0. 846 810 596 0.05%Quaternary O... 834 728 620 0.005% Oronite Quater- 562 844 208 naryCompound ATM-50. 0.01% Oronite Quater- 454 486 338 nary Compound ATM-50.0.03% Oronite Quater- 487 484 331 nary C ompound ATM-50. 0.05% OroniteQuater- 442 507 350 nary Compound ATM-50. 0.005% Cetyl Benzal- 582 1,098 247 konium Chloride. 0.01% Cetyl Benzal- 436 501 3,38

konium Chloride. 0.03% Cetyl Benzal- 320 506 358 konium Chloride. 0.05%Cetyl Benzal- 357 547 352 konium Chloride. 0.005% Lauroyl Pyri- 419 406259 dinium Chloride. 0.01% Lauroyl Pyri- 324 422 309 dinlum Chloride.0.03% Lauroyl Pyri- 344 516 366 dim'um Chloride. 0.05% Lauroyl Pyri- 593357 dinium Chloride. 0.005% Hyamine 1622.... 537 760 272 0.01% Hyamine1622...- 390 546 338 0.03% Hyaminc 1622..... 382 548 323 0.05% Hyamine1622.... 406 403 384 0.005% Hyamine 2389"" 424 922 287 0.01% Hyamine2389-.." 378 390 312 0.03% Hyamine 2389..... 328 352 303 Do 0.05%Hyamine 2389.... 335 370 306 1% Cumene Hy 1, 353 1, 543 83 droperoxide.

Do 0.005% Quaternary 0.... 694 1,063 417 0.01% Quaternary O 603 690 4170.03% Quaternary O 562 580 422 0.05% Quaternary O. 575 588 4 0.005%Oronite Quat 401 495 222 nary C ompound ATM-50. 0.01% Oronite Quater-338 370 nary Compound ATM-50. 0.03% Oronite Quater- 288 315 77 naryCompound ATM- 0.05% Oronite Quater- 312 325 nar y C ompound ATM-50.0.005% Cetyl Benzal- 412 490 konium Chloride. 0.01% Cetyl Benzal- 32 034 3 169 konium Chloride. .03 Cetyl Benzal- 335 327 195 konium Chloride.0.05% Cetyl Benzal- 316 314 konium Chloride. 0.005% Lauroyl Pyridin- 314310 189 ium Chloride. 0.01% Lauroyl Pyridln- 284 302 183 111111Chloride. 0.03% Lauroyl Pyrldin- 320 313 198 ium oiide. 0.05% LauroylPyrldin- 336 326 237 ium Chloride. 0 005% Hyamine 1622-... 389 350 1760.01% Hyamine 1622....- 326 312. 173 0.03% Hyamine 1622 319 322 1990.05% Hyamine 1622. 348 337 220 0.005% Hyamine 2389.... 431 492 2010.01% Hyamine 2389.--.- 335 338 194 0.03% 310 300 205 0.05% 315 310 1892. 420 698 256 5. 345 352 229 7. 202 319 225. 276 308 218 665 1, 265 253peroxide.

13 in Example III, as well as the subsequent examples, is quitesubstantial thus permitting batches of considerable size to be made upwithout danger of premature gelation before they can be used.

The mixtures prepared in accordance with the provisions of the precedingexamples provide hard, clear resinous bodies in every way satisfactoryin the casting art. The compositions containing the quaternary ammoniumsalts as adjuvants are characterized by their capacity to cure atrelatively mild temperatures. Indeed, in the foregoing gel tests theproducts after the tests are essentially cured to their final state butif so desired they can be subjected to further heating, for example, at90 to 150 C. for 10 minutes to 3 hours, or thereabouts, in order toattain maximum hardness.

The compositions formulated in accordance with the provisions of theexamples, before they have been gelled, can also be spread on fabrics ofglass or other materials or they can be employed to impregnate suchfabric. They can then be baked to hard durable state. Likewise, they canbe employed to impregnate or to coat preforms of fibrous materials whichare subjected to heating and pressing in a mold to form molded articlesin accordance with well known techniques. When the materials withoutfurther additions are heated to temperatures of 75 to 150 or 200 C. theyset to their final hardened thermoset resinous state.

In the preceding examples, the propylene glycol component of thepolyester may be replaced by other glycols such as diethylene glycol.Maleic acid in the polyester can also be replaced by fumaric acid or anyof the other well known alpha-beta ethylenic polycarboxylic acids.

The styrene in the examples can be replaced by other monomers containinga terminal C=CH2 group attached to a negative radical and beingrepresented by those disclosed in the aforementioned patent to Parker orin the preceding list of monomers herein contained.

The catalysts (tertiary-butyl hydroperoxide orcumene hydroperoxide, asgiven in the examples, may be replaced by any other suitable peroxide orhydroperoxide conventionally employed as a free radical initiator incompositions of the type herein disclosed and being represented in TableA. a

The forms of the invention, as herein given, are to be considered asbeing by way of illustration and not by limitation. It will be apparentto those skilled in the art that numerous modifications may be madetherein without departure from the spirit of the invention or the'scopeof the appended claims.

14 I claim:

1. A method of accelerating the polymerization of a mixture of (A) apolyester of a glycol and an alpha-beta ethylenically unsaturateddicarboxylic acid, and (B) a monomeric compound containing a CH2=Cgroup, said mixture containing as gelation inhibitor at least about 0.01per cent of a member of the class consisting of quinones and dihydricphenols, which comprises adding to said mixture at least about 0.001 percent by weight of the polyester of a quaternary ammonium salt of anonoxidizing acid at least as strong as acetic acid, in the presence ofa peroxide polymerization catalyst.

2. The method of claim 1 wherein the gelation inhibitor selected fromthe class consisting of quinones and dihydric phenols is present .in anamount of from about 0.01 per cent to 0.1 per cent by weight of thepolyester component.

3. The method of claim 1 wherein the compound containing a C 12=C groupis styrene.

4. The method of claim 3 wherein the quaternary ammonium salt istrimethylbenzyl ammonium chloride.

5. The method of claim 3 wherein the quaternary ammonium salt is lauroylpyridinium chloride.

6. A method of accelerating the polymerization of a mixture of (A) apolyester of a dihydric alcohol and a mixture of two dicarboxylic acids,one of which is alphabeta ethylenically unsaturated, and another ofwhich is free of ethylenic and acetylenic unsaturation, and (B) amonomeric compound containing a CH2=C group, said mixture containing asa gelation inhibitor at least about 0.01 per cent by Weight of thepolyester of a member of the class consisting of quinones and dihydricphenols, which comprises adding to said mixture at least about 0.001 percent by weight of the polyester of a quaternary ammonium salt of anon-oxidizing acid at least as strong as acetic acid, in the presence ofa peroxide polymerization catalyst.

7. The method of claim 6 wherein the monomeric compound containing aCH2=C group is styrene.

8. The method of claim 6 wherein the polyester component (A) is ofpropylene glycol, maleic acid and phthalic acid.

References Cited in the file of this patent UNITED STATES PATENTS2,473,801 Kropa June 21, 1949 2,554,567 Gerhart et al. May 29, 19512,578,690 Gerhart Dec. 18, 1951 2,593,787 Parker Apr. 22, 1952 2,627,510Parker Feb. 3, 1953

1. A METHOD OF ACCELERATING THE POLYMERIZATION OF A MIXTURE OF (A) APOLYESTER OF A GLYCOL AND AN ALPHA-BETA ETHYLENICALLY UNSATURATEDDICARBOXYLIC ACID, AND (B) A MONOMERIC COMPOUND CONTAINING A CH2=C<GROUP, SAID MIXTURE CONTAINING AS A GELATION INHIBITOR AT LEAST ABOUT0.01 PER CENT OF A MEMBER OF THE CLASS CONSISTING OF QUINONES ANDDIHYDRIC PHENOLS, WHICH COMPRISES ADDING TO SAID MIXTURE AT LEAST ABOUT0.001 PER CENT BY WEIGHT OF THE POLYESTER OF A QUATERNARY AMMONIUM SALTOF A NONOXIDIZING ACID AT LEAST AS STRONG AS ACETIC ACID, IN THEPRESENCE OF A PEROXIDE POLYMERIZATION CATALYST.